Aneki Kokoro to Haru no Sora

A tsundere sister with a maid fetish storms upon her brother. Some comic relief later, the brother accidentally discovers that (a) after tsun, comes dere, (b) she’s got that maid outfit and the maid spirit, and (c) so that means they both share a maid fetish.
And the rest is NOT them turning on their PS3 and playing video games =).
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